Hello,I need to propose a new organization for my company regarding storage groups. (Exch 2007).I have about 400 users and would like to get your input about how many storage groups and database I should create?I have read the microsoft recommandation but it is hard for me to make the right choice as I have not very much users.Any ideas, advice ?

The only straightforward advice is to have only one mailbox database per storage group. Aside from that, it depends a bit on what you want to accomplish and what your environment looks like. I would recommend dedicating one SG/mailbox database for top-level execs and IT staff. In the event of a disaster where you have to recover from backups, you would recover this database before the others. Keeping it small means faster recovery for these individuals. Otherwise, you can separate databases by department, or just run one big one. If you are doing replication such as CCR or SCR then you want a maximum size of 200GB. So, depending on how large your mailboxes are you can get by with one, or have more. Anyway, for a small organization you don't need to go crazy. I would do two databases, again one for top execs and IT, and another for everyone else. You can always create more and move mailboxes if it gets too big for your comfort.

You might have read this: Planning Storage Configurationshttp://technet.microsoft.com/en-us/library/bb124518(EXCHG.80).aspx But fill in the information you have about your planned mailboxes here:Exchange 2007 Mailbox Server Role Storage Requirements Calculator http://msexchangeteam.com/archive/2007/01/15/432207.aspx Download Exchange 2007 Mailbox Server Role Storage Requirements Calculator spreadsheethttp://msexchangeteam.com/files/12/attachments/entry438481.aspx I found also this very interesting when we were planningExchange 2007 Storage - Disk Sizing informationhttp://www.mmmug.co.uk/blogs/nweb/archive/2007/04/03/1098.aspxMCTS: Messaging | MCSE: S+M | Small Business Specialist